US 2024/0168070 A1 · Circuit arrangement for measuring at least one capacitor

Abstract

Circuit arrangement measuring at least one measurement capacitor having inverting amplifier with high open-circuit voltage gain, input connected to connection of at least one measurement capacitor and to connection of negative feedback capacitor, another connection of at least one measurement capacitor connected to a reference potential and another connection of negative feedback capacitor connected to output of inverting amplifier; rectifier circuit fed voltage at the output of inverting amplifier and generates at its output voltage corresponding to voltage at output of inverting amplifier; a holding capacitor buffering voltage supply of inverting amplifier and rectifier circuit, a supply voltage connection of inverting amplifier supplied with a periodic control voltage with respect to reference potential and other supply voltage connection of inverting amplifier supplied via a diode with external supply voltage, periodic control voltage generated by signal source having a control input via which level of periodic control voltage can be infinitely variably set and this control input connected to an output of a control device which compares voltage generated at output of rectifier circuit with a desired voltage and, depending on comparison, emits output signal fed to control input of signal source, until level of periodic control voltage fed to supply voltage connection of inverting amplifier reaches value at voltage generated at output of rectifier circuit matches desired voltage, if voltage present at output of rectifier circuit matches desired voltage, at least voltage present at output of control device is a measure for at least one measurement capacitor.

Claims10

Dependent claims

A circuit arrangement for measuring at least one measurement capacitor, said circuit arrangement comprising:

an inverting amplifier with a high open-circuit voltage gain, an input of which is connected to a connection of the at least one measurement capacitor and to a connection of a negative feedback capacitor, wherein another connection of the at least one measurement capacitor is connected to a reference potential and another connection of the negative feedback capacitor is connected to an output of the inverting amplifier;
a rectifier circuit which is fed the voltage at the output of the inverting amplifier and which generates at its output a voltage corresponding to the voltage at the output of the inverting amplifier;
a holding capacitor for buffering the voltage supply of the inverting amplifier and the rectifier circuit,
wherein a supply voltage connection of the inverting amplifier is supplied with a periodic control voltage with respect to the reference potential and the other supply voltage connection of the inverting amplifier is supplied via a diode with an external supply voltage,
wherein the periodic control voltage is generated by a signal source which has a control input via which the level of the periodic control voltage can be infinitely variably set and wherein this control input is connected to an output of a control device which compares the voltage generated at the output of the rectifier circuit with a desired voltage and, depending on a comparison, emits an output signal fed to the control input of the signal source, until the level of the periodic control voltage which is fed to the supply voltage connection of the inverting amplifier reaches a value at which the voltage generated at the output of the rectifier circuit matches the desired voltage, and
wherein, if the voltage present at the output of the rectifier circuit matches the desired voltage, at least the voltage present at the output of the control device is a measure for the at least one measurement capacitor.

3 more elements

A circuit arrangement for measuring at least one measurement capacitor, said circuit arrangement comprising:

an inverting amplifier with a high open-circuit voltage gain, the input of which is connected to a connection of the at least one measurement capacitor and to a connection of a negative feedback capacitor, wherein another connection of the negative feedback capacitor is connected to an output of the inverting amplifier;
a rectifier circuit which is fed the voltage at the output of the inverting amplifier and which generates at its output a voltage corresponding to the voltage at the output of the inverting amplifier;
wherein a supply voltage connection of the inverting amplifier is connected to the reference potential and the other supply voltage connection of the inverting amplifier is connected to an external supply voltage;
wherein a periodic control voltage is generated by a signal source, a control input of which is connected to an output of a control device which compares the voltage generated at the output of the rectifier circuit with a desired voltage and, depending on a comparison, emits an output signal fed to the control input of the signal source, until a level of the periodic control voltage which is fed to the other connection of the at least one measurement capacitor reaches a value at which the voltage generated at the output of the rectifier circuit matches the desired voltage, and
wherein, if the voltage present at the output of the rectifier circuit matches the desired voltage, at least the voltage present at the output of the control device is a measure for the at least one measurement capacitor.

2 more elements

Dependencies are inferred from the claim text.

Circuit arrangement for measuring at least one capacitor

Life of this patent

Circuit arrangement for measuring at least one capacitor

Life of this patent

Abstract

Claims10